1. Technical Field
This disclosure relates to a surgical instrument and, more particularly, to a surgical instrument for percutaneously accessing an operative site within a body.
2. Background of Related Art
Accessing body tissue within a body cavity or beneath the skin involves creating an opening in the skin through which different types of surgical instruments are inserted to perform various surgical or diagnostic functions. The opening of the skin to access an operative site is usually created by incising with a surgical knife or by puncturing through the skin with an instrument having a sharp tip such as a needle or an obturator. Additional instruments are then inserted through the incision to perform the surgical procedure. For example, the surgeon may use one instrument for piercing the skin to introduce a pressurized gas to inflate or distend the surgical site, an endoscope for viewing areas or objects surrounding the surgical site and other instruments for performing surgical functions such as shearing and stapling. Therefore, frequent insertions and withdrawals of surgical instruments through the skin opening are typical. These insertions and withdrawals through the skin opening may traumatize the body tissue surface layer which surrounds the skin opening, enlarge the incision or opening, and/or create room for undesired or inadvertent movement of the surgical instrument during the surgical procedure.
A trocar is one commonly used surgical instrument for creating a port of entry through the skin. A trocar guide sleeve is thus positioned for receiving surgical instruments and for facilitating passage of the surgical instruments through the skin opening. However, unless the trocar guide sleeve is somehow affixed in a stationary position with respect to the body, the frequent insertion and withdrawal of surgical instruments may move the sleeve, causing enlargement of the incision and/or trauma to the surrounding tissues. Moreover, whether or not a sleeve is fixed or held stationary relative to the body, manipulative movement of the surgical instrument while it is received in the sleeve may be inhibited.
A variety of percutaneous instruments for providing communication through the surface of body tissue are known. Known percutaneous instruments typically include a cutting or puncturing implement and some sort of safety mechanism, e.g., a spring-biased blunt styler or shielding tube which is biased to protrude beyond the distal end of the cutting implement to obstruct anatomical organs from making cutting contact with the cutting implement. Examples of devices which include spring-biased safety mechanisms and provide for percutaneous introduction include conventional Verres needles and the devices shown in U.S. Pat. No. 4,535,773 to Yoon; U.S. Pat. No. 4,556,059 to Adamson, Jr.; U.S. Pat. No. 4,601,710 to Moll; and U.S. Pat. No. 5,152,754 to Plyley et al.
Various trocars and devices for securing other surgical devices relative to a patient's body have also been proposed. See for example, U.S. Pat. No. 2,898,917 to Wallace, U.S. Pat. No. 3,487,837 to Petersen, U.S. Pat. No. 4,170,995 to Levine et al. and U.S. Pat. No. 4,915,694 to Yamamoto et al. Devices for supporting surgical instruments larger than catheters have also been proposed. For example, U.S. Pat. No. 5,073,169 to Raiken discloses a trocar support having an elastic membrane having an aperture to receive the trocar. The elastic membrane has a flat base for adhering to the patient's skin.
Notwithstanding the devices discussed above, a need remains for an instrument which minimizes the passage of surgical instruments through the skin opening, thereby minimizing potential enlargement of and trauma to the incision site. The surgical instrument disclosed herein provides such advantageous features.